2. Restart #1

If your current version of Windows loads when you restart the PC, you may have to alter the boot order in your PC’s BIOS settings. This will make your computer recognize the DVD or USB drive before the hard drive.

3. The Start of Something New

You’ll know when your PC is preparing to start Windows setup correctly when you see the Windows 8 splash screen.

During this time, your computer is unloading files in preparation for Windows 8 setup, but nothing is being deleted or uploaded yet. However, if you haven’t backed up your files, stop what you’re doing and get on that.

4. Back To Basics

Next, navigate a series of screens with some pretty basic questions. You’ll know what to do. Trust us.

5. Product Key

Here, Windows will prompt you to enter the product key, a 25-digit alphanumeric code. If you’ve purchased Windows 8 yourself, look for the key in the email confirmation you received after downloading it. If Windows 8 came preinstalled on your computer, look for a sticker with the product key somewhere on your device.

6. Acceptance Is Key

Go ahead and accept those terms and conditions.

7. Custom Job

Eventually you’ll have to choose between an “upgrade install” and a “custom install.” Choose “custom.” Upgrade seems nice, with all your files and programs already in place, but you’ll get better performance from a custom install, which removes the partition that the current operating system was installed on. Additionally, it improves the overall speed of your computer.

8. Drive Options

9. Out With the Old

Select any and all drives associated with the old operating system that you’d like to delete. You may not need to delete all partitions (like a secondary hard drive, for instance).

10. The Point of No Return

Once you confirm these deletions, you will not be able to get this data back. Did we mention that you should back up your files? Because this is the point of no return.

11. Wide Open Spaces

The partitions should all now be categorized as “unallocated space." In other words, your hard drive is empty and ready to go.

12. Pick Your Poison

You’ll now select where to install your new Windows OS, so choose the drive with unallocated space -- and click “Next.”

13. Snack Break

Windows 8 setup will now begin installing onto your computer. This usually takes about 10-20 minutes -- it's a great time to snack, take a cat nap, prancercise, etc.

14. Restart #2

Your computer will need to restart again.

15. Getting Devices Ready

You’ll then see a “Getting Devices Ready” notification that will slowly work its way up to 100%. Your screen may also flicker and go blank from time to time. Don’t worry, it's normal.

16. Restart #3

Your computer will restart for the third and final time.

17. More Basics

Next, go through a series of steps to finish the installation on your computer...

18. Personalize

First, personalize your account. Select a color and a PC name. The color helps to shape the display of Windows 8, so choose something you like. The name should be something identifiable to make your computer recognizable on the network. Think taylorswin8laptop or kylehomeoffice.

19. Settings

The next step is choosing the settings, where you can customize your network sharing, Windows Update or -- if you'd like -- automatic feedback to Microsoft options. Stick with the default (or “express”) settings if you don't have a preference.

20. Sign In

Now you'll be prompted to sign in, either with your Microsoft account, which allows you to more easily use the Windows Store and sync major settings between multiple Windows 8 computers, or with a local account, which doesn't require an email address but limits you to one device and prevents you from using features like the Windows Store.

21. Get More Snacks

You’ll go through another short series of basic questions, such as setting up a telephone number, etc., before another waiting period. Take a potty break. When you get back, you’ll have completed your clean install of Windows 8.

Congratulations, computer whiz.

22. Finishing Touches

While your computer is now running Windows 8, you may need to install a few drivers to run it the way you want. You’ll also want to upload any pictures, music or documents you saved to that hard drive. You did back up your documents, right?

Everyone needs a fresh start sometimes.

If your computer's operating system software has been modified or rendered unusable, consider applying a clean install.

A clean install — or "custom install” — removes the existing operating system and reinstalls it from scratch on the same drive. It’s an ideal move when installing a new operating system; it wipes your hard drive of unnecessary files and prevents your computer from lagging.

Here, we walk you through a clean install of Windows 8. Any issues or questions? Let us know in the comments.

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